Electronic design automation (EDA) tools, or computer aided design (CAD) tools are used by designers of electronic circuits, and specifically integrated circuits (IC) to create representations of electronic gates (e.g., transistors) and the interconnects (e.g., electrical connection) between them. Commercially available EDA tools allow designers to construct circuit layouts using a computer, which reduces circuit design cost and time.
Modern digital IC designs expend significant energy through the charging and discharging of gate and wire capacitances. Gate capacitances have scaled down with each recent generation of transistor and integrated circuit fabrication technology at a faster rate than wire capacitances. The discrepancy in the rate of capacitance scaling between gate and wire capacitances has resulted in a greater proportion of a typical design's energy being expended in charging the wires of IC designs than in previous technology generations and this trend is expected to continue.
Additionally, the performance of modern digital IC designs can be limited by the speed at which a wire can be charged and discharged by digital complementary metal oxide semiconductor (CMOS) devices that drive an output signal at conventional full digital voltage swing levels. This involves charging a capacitance inclusive of wire and gate capacitances substantially to the voltage of the attached power supply and discharging the same capacitance substantially to ground.